Masterpress 1.3.6 is a compatibility release. It resolves an edge case with shared fieldsets not working for MySQL 8 when the fieldset is limited to more than 1 post type or taxonomy or excluding any post types or taxonomies.
MEOW_FieldSetCollection :: remove( Integer $index )
Removes the field set item at the given index from this collection. This method is only appropriate for multi-set items. This method is one-based, to match the numbers presented in the user interface.
Note: You will need to call the MEOW_FieldSetCollection::update method if you wish to commit this change to the database.